Summertime is here and that means ice cream, lots of ice cream. Allulose is a low-calorie sweetener that’s used in some brands of keto-friendly ice cream. But is there a dark side to consuming lots of it?
Have you recently made the switch to an ultra low-carb diet but need an ice cream fix, stat, lest you revert back to your high-carb, insulin-spiking ways? The good news is that there’s some great keto ice cream these days, much better than in years past when biting into a spoonful risked cracking teeth as much as biting into a brick would.
To make keto-friendly ice cream you need, cream, of course, egg yolks and your choice of a low-calorie sweetener. Erythritol, the one-calorie sugar alcohol, has been a staple in ultra low-carb cooking and baking for several years now.
One of the newer alternatives is allulose, dubbed a “rare sugar” by food scientists and considered the best natural sweetener by many keto enthusiasts.
Never heard of allulose? Let’s get to know it…
What is Allulose?
Containing only 5% the calories of table sugar, allulose is a simple sugar, which is usually a recipe for disaster when it comes to metabolic health. Simple added sugars like fructose are key contributors to metabolic diseases like type 2 diabetes and obesity.
What makes allulose special is that it is found in tiny amounts in certain fruits such as dates, figs, jackfruit and dragon fruit. Because there’s so little of it in these fruits as well as in maple syrup and wheat, allulose is considered a rare sugar.
At only .2 calories per gram, allulose contains way less calories than sucrose (table sugar), which contains 4 calories per gram. (One gram of table sugar equals approximately 4 tablespoons.)
If you’re following the keto lifestyle, calories sometimes don’t matter as much as net carbs. So if you’re trying to convert the math as to how many net carbs .2 calories per gram makes, the answer is don’t worry about it.
You see, allulose technically has zero net impact carbs, meaning that there are no net carbs to run the risk of kicking you out of ketosis. How can a natural sweetener that’s not a sugar alcohol that contains carbs not have any net carbs? This paradox will be explained shortly…
Another bonus is that allulose contains approximately 70% of the sweetness that table sugar contains. This means your sweet tooth can be satisfied without craving junk carbs or sugary snacks later in the day.
How is allulose made?
Because it’s naturally found in trace amounts in a very limited number of foods, allulose is produced via a manufacturing process involving corn and enzymes. In Japan, there are tens of thousands of products with allulose. Perhaps the reason why is that Japan is the birthplace of allulose mass production, in which bacteria are used to produce enzymes that transform corn sugar into a compound called D-psicose.
Is allulose safe?
Don’t eat the whole pint of keto-friendly ice cream with allulose just yet. There hasn’t been enough research to determine the long-term effects of allulose consumption.
One of the latest research studies on allulose was published last year in the British Journal of Nutrition. The review explains that due to its structural similarity with fructose, allulose uses the same transport and distribution pathways, but in contrast to fructose, the human genome does not encode for enzymes that are able to metabolize allulose.
This keto-friendly sugar is excreted from the body, with a close-to-zero energetic yield. We just don’t know if the fact that it’s not metabolized could have a negative consequence.
The research article also cautions that studies have shown that certain harmful bacteria such as Klebsiella pneumonia are able to utilize allulose as a substrate. In other words, they can use it as fuel to proliferate in the body. “This finding has been a subject of concern, since Klebsiella pneumoniae represents an opportunistic human pathogen,” conclude the researchers.
The good news is that those studies weren’t done in living people, they were conducted in vitro (in cell cultures). Nonetheless, the researchers said the results “raises the question of whether a high dietary intake of allulose may cause an undesirable growth advantage for potentially harmful bacteria at mucosal sites such as the intestine or at systemic sites following invasive infection.”
But eating too much regular sugar can also give rise to pathogenic yeast, so there’s really nothing special about allulose in this regard.
Is a natural sugar that’s keto-friendly too good to be true? Most likely, having a little allulose here and there is safe. The best course of action is to treat keto ice cream just like regular ice cream: eat it in moderation.